Immediately to the north-east of the path by the footpath sign. GPS reading SJ 0469 3346. Three very low banks with lots of stones are visible.
Coflein gives the following description: "Three eccentrically concentric stony rings, each c.2.0m thick, 20m overall diameter, the innermost circle, c.6.0m overall diameter. Part of what is designated the 'Cwm Tywyll ritual complex'"
There is also a round cairn of 6m diameter immediately on the other side of the path. GPS reading SJ 0466 3344.
Both are on a plateau with superb 360 degree views.